Gibson solid body 1975 solid body catalog. The front cover features Carlos Santana playing one of the new L6-S guitars in natural finish. He says "I think of a guitar as a color, but this L6-S is like a rainbow".
This picture (or a cutout version thereof) was also used in the Santana Calls It his Rainbow advertisement, printed in guitar magazines circa 1976 (right).
This guitar would go on to be called the L6-S Custom (once the L6-S Deluxe was also launched - actually about the same time, or shortly after this brochure was first circulated), but at this point it was still, simply, the L6-S - see it in this catalog on page 7.
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